Processes of the kind mentioned in the introduction are used in the production of ceramic multi-layer substrates in which passive components can be integrated. Active components can be mounted on the surface of the substrate via binding technologies such as SMD, wire bonding, or flip-chip assembly. In this way, multi-functional modules are formed that are especially suitable for saving space.
A process of the kind mentioned in the introduction is known from printed document U.S. Pat. No. 6,207,905, where the superimposed layers contain a ceramic material and glass. In this case the proportion of glass and ceramic materials is about 50% by weight in each case. The glass serves here as an auxiliary sintering agent and it is created in the known process in such a way that it is recrystallized (reaction sintering). Because of the glass proportion of about 50 wt % in the known process, reaction layers only a few microns thick are formed between the individual layers of the multi-layer structure. In mounting components on the surface of the sintered stack of layers, shearing stresses can lead to a breaking of the top reaction layers, which leads to part of the top layer being torn away from the stack of layers. This problem appears more strongly when the top layer of the stack of layers is covered over its whole surface with an organic material and shearing stresses are applied to this layer.